31-504: Hyaenodonta (" hyena teeth") is an extinct order of hypercarnivorous placental mammals of clade Pan-Carnivora from mirorder Ferae . Hyaenodonts were important mammalian predators that arose during the early Paleocene in Europe and persisted well into the late Miocene . Hyaenodonts are characterized by long, often disproportionately large skulls, slender jaws, and slim bodies. They generally ranged in size from 30 to 140 cm at
62-581: A change in climate, along with the arrival of canids into Eurasia. Of the dog-like hyena lineage, only the insectivorous aardwolf survived, while the bone-crushing hyenas (including the extant spotted, brown and striped hyenas) became the undisputed top scavengers of Eurasia and Africa. The descendants of Plioviverrops reached their peak 15 million years ago, with more than 30 species having been identified. Unlike most modern hyena species, which are specialised bone-crushers, these dog-like hyenas were nimble-bodied, wolfish animals; one species among them
93-693: A hyaenodonts are generally the second upper and third lower molars . However, some hyaenodonts possessed as many as three sequential pairs of carnassials or carnassial-like molar teeth in their jaws. Hyaenodonts, like all creodonts, lacked post-carnassial crushing molar teeth, such as those found in many carnivoran families, especially the Canidae and Ursidae , and thus lacked dental versatility for processing any foods other than meat. Hyaenodonts differed from Carnivora in that they replaced their deciduous dentition slower in development than carnivorans. Studies on Hyaenodon show that juveniles took 3 to 4 years in
124-537: Is a genus of teratodontine hyaenodonts of the tribe Dissopsalini . The older species, D. pyroclasticus , lived in Kenya during the middle Miocene , while the type species, D. carnifex , lived in Pakistan and India during the middle to late Miocene. Dissopsalis is the last known hyaenodont genus. It lived alongside its relative Hyaenodon weilini , a member of the very successful genus Hyaenodon , during
155-546: Is likely that its unrivaled ability to digest the terpene excretions from soldier termites is a modification of the strong digestive system its ancestors used to consume fetid carrion. The striped hyena may have evolved from Hyaenictitherium namaquensis of Pliocene Africa . Striped hyena fossils are common in Africa, with records going back as far as the Villafranchian . As fossil striped hyenas are absent from
186-1193: The Furninha Cave in Portugal and the Genista Caves in Gibraltar . The European form was similar in appearance to modern populations, but was larger, being comparable in size to the brown hyena . The spotted hyena ( Crocuta crocuta ) diverged from the striped and brown hyena 10 million years ago. Its direct ancestor was the Indian Crocuta sivalensis , which lived during the Villafranchian. Ancestral spotted hyenas probably developed social behaviours in response to increased pressure from rivals on carcasses, thus forcing them to operate in teams. Spotted hyenas evolved sharp carnassials behind their crushing premolars, therefore they did not need to wait for their prey to die, and thus became pack hunters as well as scavengers. They began forming increasingly larger territories , necessitated by
217-809: The Mediterranean region, it is likely that the species is a relatively late invader to Eurasia, having likely spread outside Africa only after the extinction of spotted hyenas in Asia at the end of the Ice Age . The striped hyena occurred for some time in Europe during the Pleistocene, having been particularly widespread in France and Germany . It also occurred in Montmaurin , Hollabrunn in Austria ,
248-577: The Mid-Pleistocene transition . The four extant species are the striped hyena ( Hyaena hyaena ), the brown hyena ( Parahyaena brunnea ), the spotted hyena ( Crocuta crocuta ), and the aardwolf ( Proteles cristata ). The aardwolf can trace its lineage directly back to Plioviverrops 15 million years ago, and is the only survivor of the dog-like hyena lineage. Its success is partly attributed to its insectivorous diet, for which it faced no competition from canids crossing from North America. It
279-893: The family Hyaenidae ( / h aɪ ˈ ɛ n ɪ d iː / ). With just four extant species (each in its own genus ), it is the fifth-smallest family in the order Carnivora and one of the smallest in the class Mammalia . Despite their low diversity, hyenas are unique and vital components of most African ecosystems. Although phylogenetically closer to felines and viverrids , hyenas are behaviourally and morphologically similar to canids in several elements due to convergent evolution : both hyenas and canines are non- arboreal , cursorial hunters that catch prey with their teeth rather than claws. Both eat food quickly and may store it, and their calloused feet with large, blunt, nonretractable claws are adapted for running and making sharp turns. However, hyenas' grooming, scent marking , defecation habits, mating and parental behavior are consistent with
310-521: The middle ear and dentition. The lineage of Plioviverrops prospered, and gave rise to descendants with longer legs and more pointed jaws, a direction similar to that taken by canids in North America . Hyenas then diversified into two distinct types: lightly built dog-like hyenas and robust bone-crushing hyenas. Although the dog-like hyenas thrived 15 million years ago (with one taxon having colonised North America), they became extinct after
341-526: The Oligocene, but declined towards the end of the epoch, with almost the entire order becoming extinct by the close of the Oligocene . Several representatives of this order, including hyainailourids Megistotherium , Simbakubwa , Hyainailouros , Sectisodon , Exiguodon , Sivapterodon , Metapterodon , and Isohyaenodon , the prionogalid Prionogale , the teratodontid Dissopsalis and
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#1732786833677372-609: The World for extant genera. The percrocutids are, in contrast to McKenna and Bell's classification, not included as a subfamily into the Hyaenidae, but as the separate family Percrocutidae (though they are generally grouped as sister-taxa to hyenas ). Furthermore, the living brown hyena and its closest extinct relatives are not included in the genus Pachycrocuta , but in the genus Parahyaena . However, some research has suggested Parahyaena may be synonymous with Pachycrocuta , making
403-421: The ancestral bone-crushing hyenas coincided with the decline of the similarly built family Percrocutidae . The bone-crushing hyenas survived the changes in climate and the arrival of canids, which wiped out the dog-like hyenas, though they never crossed into North America, as their niche there had already been taken by the dog subfamily Borophaginae . By 5 million years ago, the bone-crushing hyenas had become
434-438: The behavior of other feliforms. Hyenas feature prominently in the folklore and mythology of human cultures that live alongside them. Hyenas are commonly viewed as frightening and worthy of contempt. In some cultures, hyenas are thought to influence people's spirits, rob graves, and steal livestock and children. Other cultures associate them with witchcraft, using their body parts in traditional medicine . Hyenas originated in
465-419: The broader context of late-Quaternary extinctions , as the late Pleistocene and early Holocene saw the disappearance of many primarily large mammals from Europe and the world. Expansion or duplication of the olfatory receptor gene family has been found in all 4 extant species, which would have led to the evolution of the more specialised feeding habits of hyenas. Expansion in immune-related gene families
496-1323: The brown hyena the only extant member of this genus. The following cladogram illustrates the phylogenetic relationships between extant and extinct hyaenids based on the morphological analysis by Werdelin & Solounias (1991), as updated by Turner et al. (2008). Protictitherium crassum "Protictitherium" cingulatum "Protictitherium" intermedium "Protictitherium" llopisi "Protictitherium" punicum " Protictitherium" gaillardi "Protictitherium" sumegense "Protictitherium" csakvarense Plioviverrops gervaisi Plioviverrops orbignyi Plioviverrops guerini Plioviverrops faventinus Plioviverrops gaudryi Tungurictis spocki Thalassictis robusta "Thalassictis" certa "Thalassictis" montadai "Thalassictis" proava "Thalassictis" sarmatica "Thalassictis" spelaea Tongxinictis primordialis Proteles cristatus (aardwolf) [REDACTED] Proteles amplidentus Ictitherium viverrinum Ictitherium ebu Ictitherium tauricum Ictitherium ibericum Ictitherium kurteni Ictitherium intuberculatum Ictitherium pannonicum Miohyaenotherium bessarabicum Hyaenotherium wongii Hyaenictitherium hyaenoides "Hyaenictitherium" pilgrimi Dissopsalis Dissopsalis ("double scissors")
527-424: The clade Ferae , closer to Pholidota than to Carnivora . However, order Creodonta is now considered to be a polyphyletic wastebasket taxon containing two unrelated clades assumed to be closely related (or ancestral) to Carnivora. Hyena Hyenas or hyaenas ( / h aɪ ˈ iː n ə z / hi- EE -nəz ; from Ancient Greek ὕαινα , hýaina ) are feliform carnivoran mammals belonging to
558-418: The dominant scavengers of Eurasia, primarily feeding on large herbivore carcasses felled by sabre-toothed cats . One genus, Pachycrocuta , was a 110 kg (240 lb) mega-scavenger that could splinter the bones of elephants . Starting in the early Middle Pleistocene Pachycrocuta was replaced by the smaller Crocuta and Hyena , which corresponds to a general faunal change, perhaps in connection to
589-410: The end of the last glacial period and a subsequent displacement of open grassland by closed forests, which favoured wolves and humans instead. However, analyses have shown that climate change alone is insufficient to explain the spotted hyena's disappearance from Europe, suggesting that other factors – such as human pressure – must have played a role. This suggests that the events must be seen within
620-482: The evolution of the feeding of termites Trinervitermes in this species. Mutations and variants in genes related to craniofacial shape were also found ( GARS , GMPR , STIP1 , SMO and PAPSS2 ). Another gene is related to protective epidermis function ( DSC1 ). The list follows McKenna and Bell's Classification of Mammals for prehistoric genera (1997) and Wozencraft (2005) in Wilson and Reeders Mammal Species of
651-480: The fact that their prey was often migratory, and long chases in a small territory would have caused them to encroach into another clan's turf. Spotted hyenas spread from their original homeland during the Middle Pleistocene , and quickly colonised a very wide area from Europe, to southern Africa and China . The eventual disappearance of the spotted hyena from Europe has traditionally been attributed to
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#1732786833677682-402: The jungles of Miocene Eurasia 22 million years ago, when most early feliform species were still largely arboreal . The first ancestral hyenas were likely similar to the modern African civet ; one of the earliest hyena species described, Plioviverrops , was a lithe, civet-like animal that inhabited Eurasia 20–22 million years ago, and is identifiable as a hyaenid by the structure of
713-550: The land bridge into North America, being the only hyena to do so. Chasmaporthetes managed to survive for some time in North America by deviating from the endurance-running and bone-crushing niches monopolized by canids, and developing into a cheetah -like sprinter. Most of the dog-like hyenas had died off by 1.5 million years ago. By 10–14 million years ago, the hyena family had split into two distinct groups: dog-like hyenas and bone-crushing hyenas. The arrival of
744-517: The largest in the group), and the much earlier-living Hyaenodon gigas (the largest species from genus Hyaenodon ), which may have been as large as 1.4 m high at the shoulder, 3.0 m long and weighed about 330 kg. Most hyaenodonts, however, were in the 5–15 kg range, equivalent to a mid-sized dog . The anatomy of their skulls show that they had a particularly acute sense of smell, while their teeth were adapted for shearing, rather than crushing. Hyaenodonts were ancestrally plantigrade , but
775-835: The last stage of tooth eruption, implying a very long adolescent phase. In North American forms, the first upper premolar erupts before the first upper molar, while European forms show an earlier eruption of the first upper molar. At least one hyaenodont lineage, subfamily Apterodontinae , was specialised for aquatic, otter -like habits. Having evolved in Europe during the Paleocene , hyaenodonts soon after spread into Africa and India , implying close biogeographical connections between these areas. Afterwards, they dispersed into Asia from either Europe or India, and finally, North America from either Europe or Asia. They were important hypercarnivores in Eurasia, Africa, and North America during
806-511: The later, larger forms were generally digitigrade or semidigitigrade. Because of their size range, it is probable that different species hunted in different ways, which allowed them to fill many different predatory niches , with small or medium-sized forms filling roles similar to mustelids or smaller felids of today while the larger forms functioned as apex predators focusing on larger prey, wielding their mighty jaws as their principal weapon as they lacked grasping forelimbs. The carnassials in
837-409: The latter may simply have moved into vacant niches after the extinction of hyaenodont species. Hyaenodonts were considerably more widespread and successful than the oxyaenids , the other clade of mammals originally classified along with the hyaenodonts as part of Creodonta . In 2015 phylogenetic analysis of Paleogene mammals, by Halliday et al., monophyly of Creodonta was supported and was placed in
868-444: The shoulder. While Simbakubwa kutokaafrika may have been up to 1,500 kg (3,300 lb) (surpassing the modern polar bear in size), this estimate is suspect due to being based on skull-body size ratios derived from felids , which have much smaller skulls for their body size. Other large hyaenodonts include two close and later-surviving relatives of Simbakubwa , Hyainailouros and Megistotherium (the latter likely being
899-460: The youngest species of genus Hyaenodon , H. weilini , survived into or evolved during the Miocene, of which, only Dissopsalis survived long enough to go extinct at the close of the Miocene. Traditionally, this has been attributed to competition with carnivorans, but no formal examination of the correlation between the decline of hyaenodonts and the expansion of carnivorans has been recorded, and
930-521: Was Ictitherium viverrinum , which was similar to a jackal . The dog-like hyenas were numerous; in some Miocene fossil sites, the remains of Ictitherium and other dog-like hyenas outnumber those of all other carnivores combined. The decline of the dog-like hyenas began 5–7 million years ago during a period of climate change, exacerbated by canids crossing the Bering land bridge to Eurasia. One species, Chasmaporthetes ossifragus , managed to cross
961-584: Was also found in the spotted hyena, striped hyena and brown hyena, which would have led to the evolution of the scavenging in these species. Mutations and variants were also found in digestion-related genes ( ASH1L , PTPN5 , PKP3 , AQP10 ). One of these digestion-related genes has variants also related to enhanced bone mineralisation ( PTPN5 ), while other have also a role in inflammatory skin responses ( PKP3 ). In aardwolves, expansion of genes related to toxin response were found ( Lipocalin and UDP Glucuronosyltransferase gene families), which would have led to